Changes in the cellular immune system and circulating inflammatory markers of stroke patients

Abstract

This study was designed to investigate dynamic changes in the cellular immune system and circulating inflammatory markers after ischemic stroke. Blood was collected from 96 patients and 99 age-matched control subjects for detection of lymphocyte subpopulations and inflammatory markers. We observed decreases in B cells, Th cells, cytotoxic T cells, and NK cells and an increase in regulatory T (Treg) cells in stroke patients on days 1, 3, and 7. Serum levels of TNF-a, C-reactive protein (CRP), IL-4, IL-6, IL-10, IL-17, IL-23, and TGF-β increased, whereas serum level of IFN-? decreased at all time points after stroke. Stroke patients with infection exhibited a similar tendency toward changes in some lymphocyte subpopulations and inflammatory markers as stroke patients without infection. After controlling for NIH Stroke Scale (NIHSS), we observed no differences in lymphocyte subpopulations between patients with anterior circulation stroke and those with posterior circulation stroke at any time point. The splenic volume correlated positively with the percentages of B cells, Th cells, and cytotoxic T cells, but negatively with Treg cells on day 3 after stroke. Infections were associated with splenic volume, leukocyte counts, percentage of Treg cells, and serum levels of CRP, IL-10, and IFN-? on day 3. Lesion volume correlated positively with CRP, IL-6, and IL-23, but negatively with IFN-? on day 3. The NIHSS showed a positive relation with IL-6 and IL-10 on day 3. Ischemic stroke has a profound effect on the systemic immune system that might explain the increased susceptibility of stroke patients to infection.

Immune changes in peripheral blood and hematoma of patients with intracerebral hemorrhage

“…Isotype control antibodies coupled to appropriate fluorescein were used in this study. The immunocytes were gated based on previous reports . Dead cells were excluded if aqua amine‐reactive dye was positive.…”

“…Infection was diagnosed with the criteria of the PANTHERIS study, which includes criteria for the diagnosis of stroke‐related pneumonia or urinary tract infection . As previously described, the NIHSS and GCS were used to evaluate the neurologic deficits and consciousness of patients on admission in the neurologic intensive care unit.…”

“…Infection was diagnosed with the criteria of the PANTHERIS study, which includes criteria for the diagnosis of stroke-related pneumonia or urinary tract infection. 33,37 As previously described, the NIHSS and GCS 38 were used to evaluate the neurologic deficits and consciousness of patients on admission in the neurologic intensive care unit. We used the modified mRS, a 7-point scale ranging from 0 (no symptoms) to 6 (death), 39,40 to assess neurologic outcomes on day 90 after symptom onset.…”

“…Sample sizes were determined with the power analysis based on pilot studies and previous data (with a type I error of 0.05, power of 0.8). 33 Statistical analysis was carried out with SPSS 13.0 (SPSS Inc., Chicago, IL, USA). Data were presented as mean (SEM) or median (range) for continuous variables and percentage (count) for categorical variables, unless otherwise indicated.…”

“…The immunocytes were gated based on previous reports. 20,[33][34][35][36] Dead cells were excluded if aqua aminereactive dye was positive.…”